JP2600904B2 - Image synthesizing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an image synthesizing method and an image synthesizing apparatus, and more particularly, to an image composed of a still image or an image having little motion and an image moving at high speed. The present invention relates to an image synthesizing method and an apparatus suitable for displaying.

<Prior Art and Problems to be Solved by the Invention> Conventionally, graphics display devices have been used in various fields, and higher resolution and higher display speed have been promoted.

However, in a conventional graphics display device,
Calculate pixel data for one screen for each new frame,
Since the new frame is displayed visually based on the calculation result, the calculation speed must be increased if the display speed is to be increased, which inevitably increases the cost of the graphics display device as a whole. Would. Further, even if the calculation ability can be increased, if the image to be displayed is complicated, the amount of calculation increases as a whole, so that there is a problem that the display speed cannot be increased much. For example,
When used as a simulator for a competitive car,
Since the background is extremely complicated, the amount of calculation for each new frame becomes enormous, and even if a graphics display device with high calculation capability is adopted, the display speed cannot be increased much.
Accordingly, since the most required moving speed of the competitive car is high, a high-speed display corresponding to this speed is required, but the competitive car must be displayed in accordance with the display speed in units of new frames. Will not get. As a result, the competitive car cannot be moved smoothly on the display screen, and the competitive car moving at a high speed is displayed discontinuously.

It should be noted that even if it is not a simulator for a competitive car, it is a complicated image as a whole, and there is a similar problem when there is an object moving at a very high speed in this image.

<Object of the Invention> The present invention has been made in view of the above-described problems, and it is possible to smoothly display a state in which an object moves at high speed in a complex image as a whole regardless of the moving speed of the object. It is an object of the present invention to provide a method and an apparatus for synthesizing an image.

<Means for Solving the Problems> In order to achieve the above object, the image synthesizing method of the present invention generates a plurality of image data at a cycle corresponding to the movement of each image, and also generates depth data. In this method, all the image data are combined and displayed based on the magnitude relationship of the depth data so that any one of the image data has priority.

In order to achieve the above object, another aspect of the present invention provides an image synthesizing method, which divides image data based on the degree of motion and generates each at a cycle corresponding to the motion, and also generates depth data. Is a method of synthesizing and displaying all the image data so that any one of the image data has priority based on the magnitude relation of.

In order to achieve the above object, an image synthesizing apparatus according to another aspect of the present invention includes a dividing unit that divides an image based on the degree of motion, and an image data and a depth data corresponding to each divided image corresponding to a motion. A plurality of image generating means for periodically generating the image data, an image holding means and a depth data holding means for respectively holding the image data and the depth data generated by each image generating means, and depth data corresponding to all the images. And selecting means for selecting any image data based on the magnitude relation.

However, it is preferable that the image holding unit and the depth data holding unit assigned to the image with a lot of motion have a dual plane configuration, and the other image holding units and the depth data holding unit have a single plane configuration.

<Operation> With the image synthesizing method of the first invention, a plurality of image data are generated at a period corresponding to the motion of each image, and
Depth data is also generated, and all image data is synthesized and displayed based on the magnitude relationship of the depth data so that any image data has priority. Therefore, image data that needs to be generated for each new frame Only a part of the image data may be displayed, the display speed can be increased, and each image data is newly generated in response to the motion, so that continuous motion can be smoothly expressed.

According to the second aspect of the present invention, the image data is divided based on the degree of movement and generated at intervals corresponding to the movement, and any one of the image data is prioritized based on the magnitude relationship between the respective depth data. Since all the image data are combined and displayed, only a part of the image data needs to be generated for each new frame, and the display can be speeded up. Since each image data is newly generated in correspondence with the motion, continuous motion can be smoothly expressed.

According to the third aspect, the image is divided by the dividing means based on the degree of movement, and the image data and the depth data corresponding to each divided image are divided by the plurality of image generating means at a period corresponding to the movement. Generate regularly. Then, the image data and the depth data generated by each image generating means are respectively held by the image holding means,
The selection means selects any one of the image data based on the magnitude relationship between the depth data corresponding to all the images. Therefore, the display is performed by the display means based on the selected image data. Remarkably high-speed display can be achieved by reducing the number of pixels, and continuous movement can be smoothly expressed.

According to the fourth aspect of the present invention, the image holding means and the depth data holding means having the dual plane configuration are assigned to an image having a lot of motion, which requires frequent generation of image data. It is possible to greatly suppress the calculation time required for obtaining the display speed from being reduced, and furthermore, a single plane image holding unit and a depth data holding unit for an image with low image data generation frequency and little movement. Since the means are assigned, the configuration can be simplified.

<Example> Hereinafter, an example will be described in detail with reference to the accompanying drawings.

FIG. 1 is a flowchart showing an embodiment of an image synthesizing method according to the present invention. In the step, an image to be displayed is divided into a plurality of images based on the degree of motion, and in the step, the presence or absence of an image without motion is determined. If it is determined that there is an image with no motion, still image data and depth data are generated in step and stored in the memory in step.

When it is determined that there is no image with no motion in the step, or after the processing of the step is performed, it is necessary to wait until the timing to update any of the images divided in the step, It is determined whether to update the image, new image data and depth data are generated only for the image to be updated in the step, and the newly generated image data and depth data are stored in the memory in the step. Then, in the step, all the images are synthesized based on the magnitude of the depth data, the image synthesized in the step is displayed, and the step is discriminated again.

Therefore, when there is a guard who walks in the course in the simulation for the competitive car, the image may be divided into the background, the guard, and the competitive car. If the division is performed in this manner, the background does not move at all like the above-described embodiment. Therefore, once the image data is generated, the image data may be simply read from the memory and displayed. In addition, since a competitive car moves at a very high speed, the image data must be updated most frequently in order to display the movement realistically. Further, since the observer moves only at a considerably low speed as compared with a competitive car, the frequency of updating the image data does not need to be too high.

That is, according to the above-described embodiment, the background may be left as it is once generated, the competitive car may be updated every new frame, and the monitor may be updated every several new frames. The scene seen from can be displayed extremely realistically. In addition, since the compositing is performed based on the depth data, a distant competitive car or the like is hidden in the near view, and the realism of the display can be significantly improved.

Although only the case where the background is divided into the background, the guard and the competitive car has been described above, it is possible to further enhance the realism by dividing the background into a portion that does not move at all and a slowly moving cloud or the like.

Further, the present invention can be applied to other simulations.

<Embodiment 2> FIG. 2 is a block diagram showing still another embodiment of the image synthesizing apparatus, wherein DDAs (21), (22)... (2n) for generating divided image data, and Display memories (31), (32) ... (3n) and depth buffers (4) for storing image data and depth data output from the DDA, respectively.
1) (42) ... (4n) and each display memory (31) (32) ... (3
LUTs (51), (52) ... (5n) that output the corresponding color data with the image data output from n) as input,
A depth data comparator (61) for inputting depth data output from all depth buffers (41) (42)... (4n) and outputting a selection signal; and any LUT using the selection signal as a switching control signal And a D / A converter (63) that converts digital data output from the selection unit (62) into RGB data and supplies the RGB data to a display unit (not shown). Have. The display memories (31) (32)... (3n) and the depth buffers (41) (42)... (4n) are connected to the processor (60) via the CPU bus (64). Accordingly, for example, when the image has no motion, the image data and the depth data generated by the processor can be written. The processor (60) divides the image and supplies necessary data to the corresponding DDA.

The operation of the image synthesizing device having the above configuration is as follows.

For a still image, the processor generates image data and depth data and stores them in the corresponding display memory and depth buffer, respectively. Then, for the moving image, the corresponding DDA generates image data and depth data at a period determined based on the moving speed, and stores them in the corresponding display memory and depth buffer, respectively.

And all depth buffers (41) (42) ... (4
By supplying the depth data read from n) to the depth data comparator (61), a selection signal indicating the image data to be displayed is generated. Based on this selection signal, the selection unit (62) The color data read from the corresponding LUT is selected and supplied to the D / A converter (63).

Therefore, the images are synthesized in a state in which the overlapping of the plurality of divided images is taken into consideration, and extremely realistic display can be achieved. That is, FIG.
When the still image shown in Fig. 7 and the moving image shown in Fig. B are combined, the moving image is not displayed unconditionally, but is displayed only when the still image is in front of the still image as shown in Fig. C. (See FIG. C), resulting in a very realistic display.

Further, if the content of each LUT is changed by the processor, a change in color tone caused by an environmental change can be easily and quickly reflected on the display.

As is clear from the above description, in this embodiment, the display memory and the depth buffer have the same hardware configuration, so that the erasing of the depth buffer can be speeded up as in the case of the display memory.

<Embodiment 3> FIG. 4 is a block diagram showing still another embodiment of an image synthesizing apparatus. The difference from the second embodiment is that the image synthesizing apparatus is read out from depth buffers (41), (42),. Depth buffer at the time of writing image data to display memories (31), (32)... (3n) (more precisely, at the time of read-modify-write) instead of the depth data comparator (61) for comparing the input depth data. (41) (42): A depth data comparator (65) for comparing depth data output from (4n) is provided,
The only difference is that a switch plane (66) that holds the comparison result data output from the depth data comparator (65) and supplies the held data as a switching control signal to the selection unit (62) is provided.

Therefore, in the case of this embodiment, the switch plane (66) is used when writing image data to each display memory.
Is written to the switch plane (6
By supplying the comparison result data read from 6) to the selection unit (62) as a switching control signal, an image can be synthesized and displayed as in the second embodiment.

It should be noted that the present invention is not limited to the above embodiment. For example, depending on the type of image, it is possible to perform band compression, and it is possible to automate image segmentation. Various design changes can be made without departing from the scope of the invention.

<Effects of the Invention> As described above, in the first invention, only a part of the image data that needs to be generated for each new frame is required, and the display can be speeded up. Since it is newly generated, a unique effect that a continuous movement can be smoothly expressed is achieved.

According to the second invention, only a part of the image data that needs to be generated for each new frame can be used, and the display can be speeded up. In addition, since each image data is newly generated in response to motion, It has the unique effect of being able to express continuous movements smoothly.

In the third invention, only a part of the image data that needs to be generated for each new frame is required, and the display can be speeded up. Each image data is newly generated in response to a motion. It has the unique effect of being able to express continuous movements smoothly.

According to the fourth aspect, the influence of the time required for calculating the moving image data is largely eliminated, and the display can be further speeded up and the configuration can be suppressed from being complicated. It works.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an embodiment of the image synthesizing method of the present invention, FIG. 2 is a block diagram showing an embodiment of the image synthesizing apparatus, FIG. FIG. 4 is a block diagram showing another embodiment of the image synthesizing apparatus. (21) (22) ... (2n) ... DDA, (62) ... Selection section, (31)
(32) ... (3n) ... display memory, (41) (42) ... (4n) ...
Depth buffer, (60) ... Processor, (61) (65)
… Depth data comparator, (66)… switch plane

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-100788 (JP, A) JP-A-63-45682 (JP, A)

Claims (4)

(57) [Claims] 1. A plurality of image data are generated at a cycle corresponding to the motion of each image, and depth data is also generated.
An image synthesizing method, comprising synthesizing and displaying all image data so that any one of the image data has priority based on the magnitude relationship of the depth data. 2. The method according to claim 1, wherein the image data is divided on the basis of the degree of the motion, and is generated at a period corresponding to the motion, and the depth data is also generated. And synthesizing and displaying all the image data. 3. A dividing means (60) for dividing an image based on the degree of movement, and a plurality of means for periodically generating image data and depth data corresponding to each divided image at a period corresponding to the movement. Image generation means (21) (22) ... (2n)
(31), (32)... (3n) and image data holding means for holding the image data and the depth data generated by the image generating means (21) (22). Means (41) (42)... (4n) and selecting means (61) (62) (65) for selecting any image data based on the magnitude relation of the depth data corresponding to all the images
(66) An image synthesizing apparatus, comprising: 4. An image holding means and a depth data holding means assigned to an image having a lot of motion have a dual plane configuration, and the other image holding means and a depth data holding means have a single plane configuration. 4. The image synthesizing device according to claim 3, wherein: